title: Porous silicon affinity chips for biomarker detection by MALDI-TOF-MS.
abstract: B-type natriuretic peptide (BNP) is an important biomarker in early diagnosis of congestive heart failure. Many efforts have been made previously to evaluate the BNP level in human plasma. We developed a porous silicon (PSi) affinity chip to detect BNP present at low concentrations in human plasma by matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) directly. The PSi surface immobilized with antibodies captured and concentrated BNP through antibody-antigen interaction specifically and sensitively. A detection limit as low as 10 pg/mL BNP in human plasma was demonstrated by mass analysis. This effective on-chip recognition, enrichment, and detection strategy could be employed in identification of biomarkers in complex body fluids in diagnoses.
authors.affiliation: State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093, Jiangsu, PR China.
authors.forename: Ya-Qing
authors.initials: YQ
authors.lastname: Chen
authors.forename: Feng
authors.initials: F
authors.lastname: Bi
authors.forename: Shi-Quan
authors.initials: SQ
authors.lastname: Wang
authors.forename: Shou-Jun
authors.initials: SJ
authors.lastname: Xiao
authors.forename: Jian-Ning
authors.initials: JN
authors.lastname: Liu
mesh_terms: D055910:Antibodies, Immobilized / Q000276:immunology / Q000378:metabolism; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000378:metabolism; D015415:Biomarkers / Q000097:blood*; D002021:Buffers; D006801:Humans; D046208:Microchip Analytical Procedures; D020097:Natriuretic Peptide, Brain / Q000097:blood* / Q000276:immunology; D016062:Porosity; D012680:Sensitivity and Specificity; D012825:Silicon / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000295:instrumentation* / Q000379:methods; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D013057:Spectrum Analysis / Q000379:methods
chemical_list: D055910:Antibodies, Immobilized; D000911:Antibodies, Monoclonal; D015415:Biomarkers; D002021:Buffers; D020097:Natriuretic Peptide, Brain; D012825:Silicon